Joint strip for concrete floors



F. 1. BORKENSTEiN. JOINT STRIP FOR CONCRETE FLOORS.

APPLICATION FILED JUNE 25.192!- Patented Sept. 19, 1922..

6 /4/ ziodgyj v 1 .1 r 4 Patented Sept. 19, 1922.

. ET D S FRANK J. BORKENSTEIN, 0F FORT WAYNE, INDIANA, ASSIGNOR TO ARTMOSAIC AND TILE COMPANY,

OF TOLEDO, OHIO, A COPARTNERSHIPCOMPOSED OF MICHAEL C.

FIORITTO, RICHARD E. WRIGHT, AND FRANK J. BORKENSTEIN.

JOINT STRIP FOR CONCRETE FLOORS.

Application filed June 25,

To all whom it may concern:

Be it known that I, FRANK J. BORKEN- .STEIN, a citizen of the UnitedStates of America, and resident of Fort Wayne, in the county of Allenand State of Indiana, have invented certain new and useful Improvementsin Joint Strips for Concrete Floors, of which the following is aspecification.

This invention relates to improvements in joint strips for concretefloors especially those formed of strata, the superstratum of which islaid after the substratum has been partially hardened, it being theintention that the joint strip shall remain permanently in and becomepart of the floor. The

object of the invention is to provide a strip r so constructed that itmay be set in the substratum of the floor while it is only partiallyhardened and so that a portion of the strip will project and be held ina vertical planea fixed distance above the top surface of thesubstratum.

Another object of the invention is to so construct the strip that theparts of the superstratum of the floor that are separated by the stripswill be protected by metal facings which abut one another.

And a further object of the invention is to provide a cushion betweenthe portions of the superstratum that are separated by the strip so asto compensate for expansion and contraction of those portions withoutcausing crumbling of their edges.

These objects are accomplished by the construction illustrated in theaccompanying drawings in which Fig. 1 is a perspective view of a stripembodying the invention; 1

. Fig. 2 is a vertical section of a floor structure in which the stripsare shown;

Fig. 3 is a perspective 'view showing the invention in a modified formand in which the cushion strip is included; and

- Fig. 4 is a vertical section of a floor structure in which is shownthe invention in the modified form.

The characters included in the description refer to parts shownon thedrawings and designated thereon by corresponding characters:'

The strip is formed of sheet metal preferably of a non-corrosivecharacter such as brass, the metal being of thin sheet or plate 1921.Serial No. 480,346.

stock. The strip has a central plane 1 at the upper edge of which is acontiguous L- shaped extension 2 and at the lower edge of the plane is asimilar contiguous L shaped extension 3, the extensions each having anoutwardly projecting wing 4 and 5 respectively that .lie in a commonplane at right angles to the plane 1, the upper edge 6 and the loweredge 7 of the strip extending in corresponding planes parallel with thatof the wings. Each wing has made therein a series of openings 8 and inthe lower portion of the strip are made a series of notches 9.

In Fig. 3 is illustrated the invention in the modified form. In thisinstance, the angular extensions 16 and 17 that are contiguousrespectively with the.upper and lower edges of the plane 18 havecorresponding wings 19 and 20 that project divergently downward and havenotches 21 formed in their edges. Also, the lower edge of the strip hasa series of notches 22 as in the former instance. Included in this formis a cushion strip 23 that is permanently positioned in the fold betweenthe plane 18 and the adjacent Wall of the angular extension 16, thecushion being formed of a material capable of being compressed, such asspongy paper,-

fioorbase 11 and leveled off in the customary manner and allowed toreach a partially set or hardened stage, at which time the strips aresetin place by pressing the strips so that their lower edges 7 areprojected into the substratum 10 and so that the wings 4 and 5 come intocontact with the upper surface 12 thereof. In thus positioning thestrips, the substratum 10 becomes partially severed by the interposedlower edge of the strip, but not entirely because of the notches 9.

When the substratum 10 has matured to a further stage of hardness thesuperstratum 13 is laid upon the substratum and covering the strips tothe level of their upper edges 6. When the floor is thus completed andafter it has hardened the surface of the superstratum is dressed bygrinding or polishing in the customary manner, the upper the samefinishing operation. Should the grinding or polishing operations, or thesubsequent wear of the floor, result in the upper edges 6 of the stripsbeing reduced so that the extension 2 becomes severed from the plane 1,the portions l land 15 of the superstratum are nevertheless protectedfrom crumbling at their adjacent edges because of their adherence to theangular extension and the plane 1 respectively. In this manner, thesevered portions of the flooring are rendered more durable and the lifeof the floor accordingly prolonged.

When the strip shown 1n Fig. 3 is employed the notched edges of thewings 19 and 20 as well as the lower edge 24 of the strip are pressedinto the substratum 25 of the floor while it is still green, thesuperstratum 26 being subsequently applied and finished as in the formerinstance; Joints formed in the superstratum by the strip in which thecushion strip 23 is included are rendered expansible owing to thepresence of the compressible strip between the plane 18 and thecontiguous angular extension .16, and thus the edges of the superstratumat the joint are rendered less liable to deterioration because ofclimatic conditions and wear.

What ll claim is 1. A joint strip for concrete floors formedwith acentral plane, there being along one.

edge thereof a contiguous L-shaped extension and at the opposite edgethereof a similar contiguous lL-shaped extension, said extensions havingcorresponding wings that project outwardly from the central plane,

'there being a series of apertures in each FRANK J. BORKENSTEIN.

Witnesses:

MATILDA METTLER, WALTER G. BURNS.

